I installed 2x LTC6811-2 and then 1x LTC6804-2 on the same board and I don't have any voltage reference output at anytime. The functional diagram in the datasheets shows that VREF1 should be always present as it's generated from V+. VREF2 is not sure what generates it.
On my board, which is a copy paste of the application note of the LTC6811 (DC2560A), no reference output is present.
DRIVE is at 5.8V, VREG is at 5V, V+ is from 10V to 30V, and there is no answer from the LTC6811.
How can I probe that this is not an internal failure of the LTC6811/LTC6804 ? I it possible to check VREGD ?
What would cause 3 new parts to fail just after installation ? ESD protected area is being used.